Grinding-mill



(Mom) T. MIGHAUT. Grinding Mill.

No. 237,037. Patented Jan. 25,188l.

- INVENTOR:

ATTORNEYS WITNESSES;

N4 PETERS. PHOTO UTNOGRAPH WASHINGTON D C UNITED STATES PATENT OFFICE.

THEODULE MIGHAUT, OF ST. PAUL, MINNESOTA.

GRINDING-MILL.

SPECIFICATION forming part of Letters Patent No. 237,037, dated January 25, 1881.

Application filed June 2, 1880.

To all whom it may concern:

Be it known that I, THEODULE MIGHAUT, of St. Paul, in the county of Ramsey and State of Minnesota, have invented a new and useful Improvement in Grinding-Mills, of which the following is a specification.

Figure 1 is a sectional elevation of the improvement. Fig. 2 is aplan view, parts being broken away. Fig. 3 is a sectional elevation taken through the line as :20, Fig. 2. Fig. is a sectional plan View taken through the line 3 y, Fig. 1.

The object of this invention is to furnish mills for grinding wheat, middlin gs, and other grains and substances, so constructed as to produce more middlings, and consequently more and better flour, than grinding-mills constructed in the ordinary manner; which will be thoroughly ventilated, so that the grindingsurfaces will not become heated; which will not require frequent cracking and furrowing or redressing to keep it in good working order, and can be run with a comparatively small amount of power. 4

Similar letters of reference indicate corresponding parts.

A represents the spindle; B, the lower or stationary grinder, and G the runner or movable grinder. The spindle A passes through the center of the stationary grinder B and supports and drives the runner O in the ordinary manner.

D is the frame within which the stationary grinder B is placed, and which is attached to and supported by the posts E.

The lands or grinding-surfaces of the grinders B O are formed of steel plates F, set edgewise, and having layers of paper or other suitable packing interposed'between them to keep them at the required distance apart. The steel plates F and the interposed packings are batted together, and are secured in a frame-work or other suitable support. With this construction the interposed packin gs, being softer than the steel plates F, will keep worn down to a lower level than the steel plates F, so that the grinders will beself-sharpenin g and will work for along time without being touched. The grinding-surfaces may be trued occasionally by means of a horizontal grinding-wheel or other suitable implement.

(No model.)

The furrows are formed of steel plates Gr, secured to the frame-work that confines the steel plates F, or to other suitable supports. The plates G are perforated with numerous holes, which, in the lower or stationary grinder, B, are made of such a size as to allow the flour and middlings to pass through. For some kinds of grain the perforations of the steel plates G may be made circular, and for other kinds of grain they may be elongated or omitted. The perforations in the plates G of the runner G are designed to admit air to the space between the grinders B O, to keep the grinding-surfaces from becoming heated. The bran escapes at the skirts of the grinders B G into the space between the said grinders and the curb H, and passes out through a spout, I. The curb H rests upon the frame D. The flour and middlings pass through the stationary grinder and are received upon the bottom board, J, which is placed at a little distance below the said grinder, rests against the downwardly-projecting edge of the band of the grinder B, and is supported upon brackets K, attached to the posts E. In the bottom J is formed an opening, L, through which the flour and middlings pass out and are conducted into some suitable receiver.

To the spindle A, within the space between the lower grinder, B, and the bottom J, is attached a scraper, M, which, as the spindle A revolves, pushes the flour and middlings out through the opening L, and thus insures its prompt discharge and prevents clogging.

To the upwardly-projecting edges of the outer and inner bands of the runner O is attached a top board, N, which is so placed as to leave an air-chamber between it and the back of the said runner. In the top board, N, are formed a number of apertures, which are closed by plates or hoods 0. To the rear parts of the plates 0 are attached, or upon them are formed, the ends. of springs P, the other ends of which are attached to the top board, N, and which are so formed as to hold the forward ends of the plates 0 raised, so that as the runner O revolves the plates 0 will gather air and guide it into the air-chamber beneath the top board, N, and force it through the perforated plates G into the space between the grinders B O.

To the forward inner corner of each of the plates 0 is attached a rack-bar, Q, which projects downward through the opening in the board N. and with the teeth of which engages a pawl, It, pivoted to the board N, and held forward against the rack-bar Q by a spring, S. The free end of the pawl It projects within the eye of the runner C, so that the said pawl may be withdrawn from the rack-bar Q by holding a stick or other suitable implement within the eye of the runner O in such a position that the projecting ends of the said pawls, as the runner revolves, will strike against the said stick. As the pawls R are withdrawn from the rack-bars (g the plates 0 are raised by the springs I, so as to collect more air. The plates are forced down more or less to diminish the force of the air-current by means of a lever, T, pivoted in a slot in the top board of the curb II, so that the lower end of the said lever can be held at any desired distance from the board ,I\' for the plates 0 to strike against and be forced down to that point, where they will be held by the rack-bar Q and the spring-pawls It S. In this way the force of the air-current can be regulated as circumstances may require.

I have described the improvement as applied to mills for grinding grain and middlings, but do not; limit myself to that use, as it may be applied with equal advantage to mills for grinding various other substances.

Having thus fully described myinventiou, I claim as new and desire to secure by Letters Patent- 1. The combination, with grinders B G, of the board N, hoods O, springs P, perforated board G, and lever T, as and for the purpose specified.

2. In a grinding-mill, the combination, with the runner (J, having openings, and the perforated steel plates G, of the top board, N, forming an air-chamber, and the plates 0, having springs P, and racks and spring-pawls Q R S, substantially as herein shown and described.

TH EODULE MICHAUT.

Witnesses:

II. KOOGAN, U. ANDERSON. 

